Research Progress on Detection of New Psychoactive Substance Piperazines in vivo.

Piperazines are a class of new psychoactive substances with hallucinogenic effects that affect the central nervous system by affecting the level of monoamine neurotransmitters. Abuse of piperazines will produce stimulating and hallucinogenic effects, accompanied by headache, dizziness, anxiety, insomnia, vomiting, chest pain, tachycardia, hypertension and other adverse reactions, and may even cause cardiovascular diseases and multiple organ failure and lead to death, seriously affecting human physical and mental health and public safety. The abuse of new psychoactive substance piperazines has attracted extensive attention from the international community. The study of its pharmacological toxicology and analytical methods has become a research hotspot in the field of forensic medicine. This paper reviews the in vivo processes, sample treatment and analytical methods of existing piperazines, in order to provide reference for forensic identification.

Left atrial appendage closure in conjunction with radiofrequency ablation: Effects on left atrial functioning in patients with paroxysmal atrial fibrillation.

Objective: In the present study, we investigated the impact of left atrial appendage closure (LAAC) following catheter ablation (CA) on the left atrial structure and functioning of patients with paroxysmal atrial fibrillation (AF). Methods: Patients with paroxysmal AF were enrolled in this single-center prospective cohort study between April 2015 and July 2021; 353 patients received CA alone, while 93 patients received CA in combination with Watchman LAAC. We used age, gender, CHA2DS2-VASc, and HAS-BLED scores as well as other demographic variables to perform propensity score matching. Patients with paroxysmal AF were randomly assigned to the CA combined with Watchman LAAC group (combined treatment group) and the simple CA group, with 89 patients in each group. The left atrial structure, reserve, ventricular diastole, and pump functions and their changes in patients were assessed using routine Doppler echocardiography and 2D speckle tracking echocardiography over the course of a 1-year follow-up. Results: At 1-week follow-up, the reserve, ventricular diastole, and pump functions of the left atrium (LA) increased in both groups; these functions were gradually restored at the 1- to 3-month follow-up; they were close to or returned to their pre-operative levels at the 3-month follow-up; and no significant differences were found compared with the pre-operative levels at the 12-month follow-up. In the first 3 months, the reserve (Ƹ, SRs) and pump functions (SRa) in the combined treatment group decreased significantly when compared with the simple CA group, and the differences were statistically significant. Conclusion: Patients with paroxysmal AF may experience a short term, partial effect of LAAC on LA reserve and pump functions, which are gradually restored and the effect disappears by 12 months.

[A multicenter study of coronary artery disease and its risk factors in rheumatoid arthritis in China].

OBJECTIVE: To learn about the prevalence and risk factors of coronary artery disease (CAD) in rheumatoid arthritis (RA). METHODS: Data were obtained from a 12-month retrospective investigation of the patients with RA, randomly selected from Departments of Rheumatology and Immunology in 21 big hospitals in China. The data were collected about their social conditions, clinical conditions, medications associated with RA, such as disease modifying anti-rheumatic drugs (DMARDs), non steroidal anti-inflammatory drugs (NSAIDs), glucocorticoid, biologic agents. A nonparameter test and multivariate logistic regression analysis were performed. RESULTS: In the study, 960 patients were enrolled. The prevalence of CAD was 3.5% in China, which was obviously higher than that of normal people. The prevalence of overweight and obesity, smoking, hypertension, diabetes mellitus, hypercholesterolemia and cerebrovascular disease were 35.1%, 12.3%, 17.0%, 7.7%, 0.4% and 3.0%, respectively. Compared with the control group, the CAD group had higher age [(64.7±9.3) years vs. (52.3±14.0) years,P<0.001], more rheumatoid nodules (14.7% vs. 3.1%,P=0.005), lower rate of hydroxychloroquine (HCQ) use (5.9% vs. 22.6%,P=0.021), higher prevalence rates of lung interstitial disease (17.5% vs. 7.0%,P<0.001), diabetes mellitus and hypertension (29.4% vs. 7.0%,P<0.001; 38.2% vs. 16.2%,P=0.001). There was no obvious correlation of CAD in RA with joint deformity, rheumatoid factor (RF) titer, glucocorticoid use, hypercholesterolemia and body mass index (BMI). Multivariate analysis showed higher age, diabetes mellitus and hypertension were independent predictors of CAD, and the use of HCQ was a protective factor of CAD. CONCLUSION: The prevalence of CAD is 3.5%. Higher age, diabetes mellitus and hypertension are independent predictors of CAD, and the use of HCQ is a protective factor of CAD.

[Survey of tumor necrosis factor inhibitors application in patients with rheumatoid arthritis in China].

OBJECTIVE: To investigate the current status of tumor necrosis factor (TNF) inhibitors application in rheumatoid arthritis (RA) patients in China and to analyze the related factors. METHODS: A retrospective survey was conducted in 21 hospitals from different parts of China. The patients with RA were randomly enrolled. Data of their social backgrounds, clinical conditions, usage and adverse effects of TNF inhibitors were collected. The costs of TNF inhibitors and the indirect costs of the disease were calculated. A multivariate Logistic regression analysis was performed to analyze the factors related to TNF inhibitors application. RESULTS: In the study, 1 095 RA patients from July 2009 to November 2010 were enrolled, of whom 112 had received TNF inhibitors, representing 10.2% of the total patients. The patients who received etanercept and infliximab were 7.4% (86/1 095) of the patients and 2.4% (26/1 095), respectively. There were 0.5% of the patients (5/1 095) who had received both of the TNF inhibitors. The patients who had accepted etanercept and treatment duration for less than 3 months and 3-6 months accounted for 38.5% and 25.0% respectively, while those treated with Infliximab were 38.1%. Their health assessment questionnaire (HAQ) scores were 1.1, 0.5 and 0.1, corresponding to treatment duration of infliximab for less than 3, 3-6 and 6-9 months and those were 1.3, 1.0, 0.3 corresponding to treatment duration of etanercept, respectively. Infliximab costs were RMB 24 525.0, 69 300.0 and 96 800.0 Yuan and etanercept costs were RMB 7 394.8, 9 158.6, 54 910.9 Yuan, respectively. Indirect costs for RA patients who accepted infliximab for less than 3, 3-6 and 6-9 months were RMB 365.6, 0 and 158.9 Yuan and those who accepted etanercept were RMB 2 158.4, 288.5 and 180.1 Yuan, respectively. Allergy and infection were the main side-effects of etanercept and both happened in 3.5% of all the patients. Liver damage happened in 2.3% of all the patients, while allergy and infection happened in 6.5% of all the patients who accepted infliximab. Logistic regression analysis showed that patients with higher education experience increased the odds of entering the TNF inhibitors group (OR: 1.292, 95%CI: 1.132-1.473, P=0.000). CONCLUSION: About one-tenth of RA patients in China have accepted TNF inhibitors. Higher education experience is the key factor for using TNF inhibitors.

Preparation of anti-salbutamol antibody based on a new designed immunogen and development of a heterologous indirect ELISA for detection of salbutamol residue.

To synthesize salbutamol immunogen and develop an enzyme immunoassay (ELISA), a new salbutamol immunogen was synthesized using 4-aminobenzoic acid as a linker to connect hapten with carrier protein. An enzyme immunoassay based on the antibody prepared was developed and applied to detect salbutamol residue spiked in swine liver. An unusual coating antigen, clenbuterol-ovalbumin (OVA) conjugate instead of salbutamol-OVA conjugate, was used in the immunoassay and the results were discussed based on the structures of related compounds. The antibodies showed high sensitivity in the heterologous assay when using clenbuterol-OVA as a coating antigen, with an IC50 value of 8.97 ng mL(-1) toward salbutamol. The antibodies prepared showed high cross-reactivity with clenbuterol (107%) and were promising for the simultaneous determination of salbutamol and clenbuterol residues in food and food products. Recovery rates from the salbutamol-spiked swine liver samples were in the range of 70%-99%, while the intra-assay and inter-assay coefficients of variation were <13.3% and <14.3%, respectively. In summary, the antibodies of salbutamol have been successfully prepared. Sensitive and stable analysis for the detection of salbutamol residues in swine liver was obtained based on the competitive ELISA methods developed in this study.

(S,R,Rp)-N,N-Dimethyl-1-{2-[(1-phenyl-ethyl)amino-meth-yl]ferrocen-yl}ethanamine.

The title chiral ferrocene compound, [Fe(C(5)H(5))(C(18)H(25)N(2))], contains one planar and two central chiral centers. It is of inter-est with respect to asymmetric catalysis. The absolute configuration of the planar chirality is Rp at the ferrocene group and those of the two C chiral centers are R at the CH carbon of the ethanamine unit and S at the CH carbon of the phenyl-ethyl-amino substituent. In the ferrocenyl unit, the cyclo-penta-dienyl (Cp) rings are planar, with maximum deviations of 0.002 (2) Šfor the substituted and 0.008 (3) Šfor the unsubstituted Cp ring. The dihedral angle between the ring planes is 2.12 (15)° and the rings are twisted slightly from an eclipsed conformation by 7.06-7.60°.

A new ratiometric fluorescent probe for rapid, sensitive and selective detection of endogenous hydrogen sulfide in mitochondria.

We have developed a new ratiometric fluorescent probe composed of a coumarin-merocyanine dyad based on the FRET mechanism. The probe showed clear dual-emission signal changes in blue and red spectral windows upon addition of H2S in a dose dependent manner under a single wavelength excitation. The probe targeted mitochondria with high selectivity and sensitivity toward H2S.

A NBD-based simple but effective fluorescent pH probe for imaging of lysosomes in living cells.

NBDlyso with lysosome-locating morpholine moiety has been developed as a high selective and sensitive fluorescent pH probe. This probe can respond to acidic pH (2.0-7.0) in a short time (less than 1 min) and not almost change after continuously illuminated for an extended period by ultraviolet light. The fluorescence intensity of NBDlyso enhanced 100-fold in acidic solution, with very good linear relationship (R(2) = 0.996). The pKa of probe NBDlyso is 4.10. Therefore, NBDlyso was used to detect lysosomal pH changes successfully. Besides, X-ray crystallography was used to verify the structure of NBDlyso, and the recognition mechanism involving photo-induced electron transfer was interpreted theoretically by means of DFT and TDDFT calculations skillfully when NBDlyso comes into play under the acidic condition. This probe showed good ability to sense pH change in living cell image.

Synthesis of novel boron chelate complexes and proposed mechanism of new rearrangement.

We synthesized novel boron chelate complexes by the reaction of pyrazoline derivatives and boron trifluoride diethyl etherate followed by a new rearrangement. The structures of the compounds were characterized by IR, NMR and HRMS, especially, a typical compound 3c was confirmed by X-ray single crystal analysis. We proposed a mechanism of the rearrangement. Moreover, the absorption and fluorescence spectroscopy of these compounds were measured.

Novel pyrazoline-based selective fluorescent probe for the detection of hydrazine.

A novel pyrazoline-based fluorescent probe, 2-[4-(3,5-diphenyl-4,5-dihydro-pyrazol-1-yl)-benzylidene]-malononitrile, with a simple structure and low detection limit (6.16×10(-6)M) for the detection of hydrazine is designed and synthesized. The probe responds selectively to hydrazine over other molecules with marked fluorescence enhancement. The probe can detect hydrazine effectively at pH 5.0-9.0 with a special emission wavelength at 520nm. Moreover, the probe can be used to detect hydrazine from variety of natural source water.

A dansyl based fluorescence chemosensor for Hg(2+) and its application in the complicated environment samples.

We have developed a novel fluorescent chemosensor (DAM) based on dansyl and morpholine units for the detection of mercury ion with excellent selectivity and sensitivity. In the presence of Hg(2+) in a mixture solution of HEPES buffer (pH 7.5, 20 mM) and MeCN (2/8, v/v) at room temperature, the fluorescence of DAM was almost completely quenched from green to colorless with fast response time. Moreover, DAM also showed its excellent anti-interference capability even in the presence of large amount of interfering ions. It is worth noting that DAM could be used to detect Hg(2+) specifically in the Yellow River samples, which significantly implied the potential applications of DAM in the complicated environment samples.

Remission of rheumatoid arthritis and potential determinants: a national multi-center cross-sectional survey.

The aim of this study is to investigate the remission rate of rheumatoid arthritis (RA) in China and identify its potential determinants. A multi-center cross-sectional study was conducted from July 2009 to January 2012. Data were collected by face-to-face interviews of the rheumatology outpatients in 28 tertiary hospitals in China. The remission rates were calculated in 486 RA patients according to different definitions of remission: the Disease Activity Score in 28 joints (DAS28), the Simplified Disease Activity Index (SDAI), the Clinical Disease Activity Index (CDAI), and the American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) Boolean definition. Potential determinants of RA remission were assessed by univariate and multivariate analyses. The remission rates of RA from this multi-center cohort were 8.6% (DAS28), 8.4% (SDAI), 8.2% (CDAI), and 6.8% (Boolean), respectively. Favorable factors associated with remission were: low Health Assessment Questionnaire (HAQ) score, absence of rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP), and treatment of methotrexate (MTX) and hydroxychloroquine (HCQ). Younger age was also predictive for the DAS28 and the Boolean remission. Multivariate analyses revealed a low HAQ score, the absence of anti-CCP, and the treatment with HCQ as independent determinants of remission. The clinical remission rate of RA patients was low in China. A low HAQ score, the absence of anti-CCP, and HCQ were significant independent determinants for RA remission.

A new Schiff base fluorescent probe for imaging Cu2+ in living cells.

A novel probe based on ferrocenyl-1,3,4-thiadiazol-containing Schiff base was synthesized by the reaction of 5-ferrocenyl-1,3,4-thiadiazol-2-amine and 4-(diethylamino)salicylaldehyde, and characterized by IR, NMR, HRMS and X-ray analysis. UV-vis spectral and fluorescence property of the probe were investigated. The probe can be used to colorimetric sensitive and selective fluorescent recognition of Cu(2+) in buffer solution. Moreover, the probe can detect Cu(2+) by electrochemical method. Additionally, the Schiff base was successfully used as a selective and sensitive fluorescent probe for monitoring Cu(2+) ions in living cells.

Novel chiral ferrocenylpyrazolo[1,5-a][1,4]diazepin-4-one derivatives--synthesis, characterization and inhibition against lung cancer cells.

A series of novel 2-ferrocenyl-7-hydroxy-5-phenethyl-5,6,7,8-tetrahydro-4H-pyrazolo[1,5-a][1,4]diazepin-4-one derivatives with optical activity (2) was synthesized in the microwave-assisted condition and characterized by means of IR, (1)H NMR and mass spectroscopy, and furthermore confirmed by X-ray analysis of a representative compound (R)-2a. Preliminary biological evaluation showed that some compounds could suppress the growth of A549, H322 and H1299 lung cancer cells. Among the tested compounds, 2b-d were more effective and might perform their action through cell cycle arrest for A549 cell. Whereas these compounds inhibited growth of H1299 and H322 cells by inducing apoptosis. The anti-tumor activities of these compounds were related to the nature of substituents in benzene moiety. In addition, the results indicated also that compounds 2b-d possessed notable cytotoxicity and selectivity for A549 vs H1299 and H322 lung cancer cells.

Synthesis, X-ray crystal structure and optical properties of novel 5-(3-aryl-1H-pyrazol-5-yl)-2-(6-methoxy-3-methylbenzofuran-2-yl)-1,3,4-oxadiazole.

A series of novel 5-(3-aryl-1H-pyrazol-5-yl)-2-(6-methoxy-3-methylbenzofuran-2-yl)-1,3,4-oxadiazole derivatives has been synthesized from 6-methoxy-3-methylbenzofuran-2-carboxylic acid and ethyl 3-aryl-1H-pyrazole-5-carboxylate. The structures of compounds obtained were determined by IR, (1)H NMR and HRMS spectra. Typically, the spatial structure of compound 7e was determined by using X-ray diffraction analysis. UV-vis absorption and fluorescence spectral characteristics of the compounds in dichloromethane and acetonitrile were investigated. The results showed that the absorption maxima of the compounds vary from 321 to 339 nm depending on the substituents in N-1 position of pyrazole moiety and para position of benzene moiety. The maximum emission spectra of compounds in two different solvents were mainly dependent on groups in N-1 position of pyrazole moiety. The intensity of absorption and fluorescence was also correlated with substituents on the aryl ring bonded to pyrazole moiety. In addition, the absorption and emission spectra of these compounds change with increasing solvent polarity.

Development of an electrochemical immunoassay for detection of gatifloxacin in swine urine.

To detect gatifloxacin (GAT) residue in swine urine, an electrochemical immunoassay was established. An indirect competitive immunoassay was developed, in which the coating antigen is immobilized in an enzyme-linked immunosorbent assay (ELISA) plate and GAT residue from the sample competes with the limited binding sites in added anti-GAT antibody. Horseradish peroxidase (HRP) conjugated to goat anti-rabbit IgG was used as the enzymatic label. A carbon fiber working electrode was constructed and current signals were detected by using hydrogen peroxide as a substrate and hydroquinone as an electrochemical mediator. The electrochemical immunoassay was evaluated by analysis of GAT in buffer or swine urine and an average value of half inhibition concentration (IC(50)) of 8.9 ng/ml was obtained. Excellent specificity of the antibody was achieved with little cross-reaction with lomefloxacin (3.0%), ciprofloxacin (3.0%), and ofloxacin (1.9%) among commonly used (fluoro)quinolones. In conclusion, the immunoassay system developed in this research can be used as a rapid, powerful and on-site analytical tool to detect GAT residue in foods and food products.

Synthesis, single-crystal characterization and preliminary biological evaluation of novel ferrocenyl pyrazolo[1,5-a]pyrazin-4(5H)-one derivatives.

A series of novel ferrocenyl pyrazolo[1,5-a]pyrazin-4(5H)-one derivatives was synthesized and characterized by 1H NMR, 13C NMR, IR, HRMS and X-ray diffraction analysis. Preliminary evaluation of biological applications showed that the compounds 6c and 6f inhibit the growth of A549 cells in dosage-dependent manners through cell cycle arrest.